On Monday (March 11), Timothy Jordan, a senior developer advocate for the project, gave a demonstration to journalists and delegates of the eyewear's functionality and usability with apps.

He showed off how eye movements control the Android-powered device, including that looking up activates the screen and head movements scroll through the various pages.

The device has a camera and supports voice commands for Google search. But Jordan also showed off a range of third-party apps that are supported by Google Glass.

Breaking news from The New York Times can be delivered hourly to the headset. Using the 'look up' gesture shows off photos and headlines, although articles are not shown with the full text as it would be too difficult to read by the user.

Popular note-taking service Evernote has been integrated to allow users to take photos on Google Glass and then share them on Evernote's Skitch service.

According to The Verge, Jordan outlined a scenario involving someone taking a picture at a meeting using Glass and Skitch, and then adding notes later on using a tablet or other device.

Path has a Google Glass service that pops up notifications right in the headset if someone shares a photo on the social network.

"Path sends me pictures from the people I know really well and the people that I love," Jordan told the audience.

"I can tap on any one of them to comment or choose an emoticon without breaking my stride. It's made for Glass, it's timely, and it's never really unexpected. It's a community I already curated on Path."

Google has also tailored Gmail for the service, allowing users to reply to important emails from the device.

Google Glass wearers are presented with the message subject line and a photo of the sender if available, and then they can reply using the voice dictation system.

Jordan advised any other developers interested in Glass that they should ensure to design their apps specifically for the headset, rather than just porting over existing services.

The nature of the device, as it is worn on a user's face, means that apps must be kept simple and not assault the wearer with unnecessary information.

For example, he said that Gmail on Google Glass has a feature to only receive emails marked as urgent, in order to avoid the person being bombarded with trivial messages and junkmail.

Google is currently ramping up its new eyewear project and is expected to launch the product by the end of the year.